I thought about this a bit and, in addition to what you said:
Let's assume you have 2 siblings in their 30s who are romantically interested in one another, they're both independent financially and there's no power imbalance between them.
If you're in a position where both parties can consent, does the law even matter? Is the neighbor gonna call the police? Is the police gonna investigate and arrest them? I highly doubt it. I guess you can't get married.
Generally incest is a social construct, aside from power dynamics, even horizontal (e.g. siblings biological, step, whatever) incest suggests some dysfunction in the family dynamic when growing up, because we know things like the Westermarck effect make incest less likely.
But there's edge cases. Like people who were adopted and never met in childhood, like it's not really incest, though there's obviously genetic concerns which makes it advisable for them to not have kids (with each other).
![[CW: Bestiality, SV] Liberalism](https://hexbear.net/pictrs/image/376d8b8a-85c2-4447-8a2d-4b2223703259.jpeg){kind=link}
spoiler
I thought about this a bit and, in addition to what you said:
Let's assume you have 2 siblings in their 30s who are romantically interested in one another, they're both independent financially and there's no power imbalance between them.
If you're in a position where both parties can consent, does the law even matter? Is the neighbor gonna call the police? Is the police gonna investigate and arrest them? I highly doubt it. I guess you can't get married.
I feel like there are certain subjects where it's just for the best not to overthink it
Using them as ideological gotchas says a lot more about them then it does about society
Something being pointless to think about has never stopped me from overthinking it
train of thought goes choo choo
Generally incest is a social construct, aside from power dynamics, even horizontal (e.g. siblings biological, step, whatever) incest suggests some dysfunction in the family dynamic when growing up, because we know things like the Westermarck effect make incest less likely.
But there's edge cases. Like people who were adopted and never met in childhood, like it's not really incest, though there's obviously genetic concerns which makes it advisable for them to not have kids (with each other).